Helleborus plant named ‘EMMA’

ABSTRACT

A new and distinct cultivar of  Helleborus  plant named ‘Emma’, characterized by its upright, outwardly spreading and mounded plant habit; dark green-colored leaves; early and freely flowering habit; long flowering period; and light green-colored flowers.

Botanical designation: Helleborus×nigercors.

Cultivar denomination ‘EMMA’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Helleborus plant, botanically known as Helleborus×nigercors, and hereinafter referred to by the name ‘Emma’.

The new Helleborus plant is a product of a planned breeding program in Oostkamp, Belgium. The objective of the breeding program was to create new vigorous Helleborus cultivars with early and freely flowering habit.

The new Helleborus plant originated from a cross-pollination conducted by the Inventor in Oostkamp, Belgium in January, 2003 of a proprietary selection of Helleborus×nigercors identified as code number 80-0062, not patented, as the female, or seed, parent with a proprietary selection of Helleborus×nigercors identified as code number 80-0061, not patented, as the male, or seed, parent. The new Helleborus plant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated cross-pollination grown in a controlled greenhouse environment in Oostkamp, Belgium in January, 2005.

Asexual reproduction of the new Helleborus plant by tissue culture in a controlled laboratory environment in Lochristi, Belgium since May, 2005, has shown that the unique features of this new Helleborus plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Helleborus have not been observed under all possible environmental conditions. The phenotype may vary somewhat with variations in environment and cultural practices such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘Emma’. These characteristics in combination distinguish ‘Emma’ as a new and distinct cultivar of Helleborus:

-   -   1. Upright, outwardly spreading and mounded plant habit.     -   2. Dark green-colored leaves.     -   3. Early and freely flowering habit.     -   4. Long flowering period.     -   5. White-colored flowers that become greenish purple with         development.

Plants of the new Helleborus differ from plants of the female parent selection in the following characteristics:

-   -   1. Plants of the new Helleborus are stronger than plants of the         female parent selection.     -   2. Plants of the new Helleborus and the female parent selection         differ in flower bud color as plants of the female parent         selection have white-colored flower buds.

Plants of the new Helleborus differ from plants of the male parent selection in the following characteristics:

-   -   1. Plants of the new Helleborus flower earlier than plants of         the male parent selection.     -   2. Plants of the new Helleborus have longer lasting flowers than         plants of the male parent selection.

Plants of the new Helleborus can be compared to plants of Helleborus ‘HGC Silvermoon’, disclosed in U.S. Plant Pat. No. 15,639. Plants of the new Helleborus differ primarily from plants of ‘HGC Silvermoon’ in the following characteristics:

-   -   1. Plants of the new Helleborus are more vigorous than plants of         ‘HGC Silvermoon’.     -   2. Plants of the new Helleborus have darker green-colored leaves         than plants of ‘HGC Silvermoon’.

BRIEF DESCRIPTION OF THE PHOTOGRAPH

The accompanying colored photograph illustrates the overall appearance of the new Helleborus plant, showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photograph may differ slightly from the color values cited in the detailed botanical description which accurately describe the colors of the new Helleborus plant.

The photograph comprises a side perspective view of a typical flowering plant of ‘Emma’ grown in a container.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photograph and following observations, measurements and values describe plants grown in Maasdijk, The Netherlands in 2-liter containers during the late winter in an outdoor nursery and under conditions which closely approximate commercial Helleborus production. During the production of the plants, day temperatures ranged from −2° C. to 25° C. and night temperatures ranged from −5° C. to 15° C. Plants had been growing for 17 months when the photograph and the description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 2001 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical classification: Helleborus×nigercors ‘Emma’. -   Parentage:     -   -   Female, or seed, parent.—Proprietary selection of             Helleborus×nigercors identified as code number 80-0062, not             patented.         -   Male, or pollen, parent.—Proprietary selection of             Helleborus×nigercors identified as code number 80-0061, not             patented. -   Propagation:     -   -   Type.—By tissue culture.         -   Time to initiate roots.—About 60 days.         -   Time to produce a rooted young plant.—About six months.         -   Root description.—Thick to thin, fleshy; white to brown in             color.         -   Rooting habit.—Sparse; moderately branching. -   Plant description:     -   -   Plant form and growth habit.—Herbaceous perennial; upright,             outwardly spreading and mounded plant habit; flattened             globular; moderately vigorous growth habit.         -   Plant height.—About 17.4 cm.         -   Plant diameter (area of spread).—About 41.6 cm. -   Foliage description:     -   -   Arrangement.—Palmately compound with five leaflets per leaf.         -   Leaf length.—About 15.8 cm.         -   Leaf width.—About 17.2 cm.         -   Leaflet length.—About 11.3 cm.         -   Leaflet width.—About 4 cm.         -   Leaflet shape.—Elliptic to slightly ovate to obovate.         -   Leaflet apex.—Acute.         -   Leaflet base.—Attenuate.         -   Leaflet margin.—Serrate.         -   Leaflet texture, upper and lower surfaces.—Smooth, glabrous;             leathery.         -   Leaflet venation pattern.—Pinnate.         -   Leaflet color.—Developing leaves, upper surface: Close to             N137B. Developing leaves, lower surface: Close to N199A             tinged with between 146A and 152A. Fully developed leaves,             upper surface: Between 139A and N189A; venation, close to             148D. Fully developed leaves, lower surface: Between 147A to             147B and 189A; venation, close to 177A to 177B.         -   Petiole.—Length: About 11.3 cm. Diameter: About 5 mm.             Texture, upper and lower surfaces: Smooth, glabrous. Color,             upper and lower surfaces: Close to 146A tinged with close to             147A. -   Flower description:     -   -   Flower shape and habit.—Single rotate flowers arranged in             terminal panicles; freely flowering habit, about 75 flowers             developing per plant; flowers face upright to outwardly;             petals not observed.         -   Fragrance.—Not detected.         -   Natural flowering season.—Long flowering period; plants             flower throughout the late winter in The Netherlands.         -   Flower longevity on the plant.—About ten days; flowers not             persistent.         -   Flower buds.—Length: About 2 cm. Diameter: About 1.1 cm.             Shape: Ovate. Color: Between 176B and 177B; with             development, color becoming closer to 145C.         -   Inflorescence height.—About 17.4 cm.         -   Inflorescence diameter.—About 11.9 cm.         -   Flowers.—Diameter: About 5.8 cm. Depth (height): About 2.2             cm.         -   Sepals.—Arrangement: About five in a single whorl. Length:             About 3.3 cm. Width: About 2.3 cm. Shape: Ovate to broadly             ovate. Apex: Rounded. Base: Obtuse. Margin: Entire. Texture,             upper and lower surfaces: Smooth, glabrous. Color: When             opening, upper surface: Between 145D and 150D. When opening,             lower surface: Close to 150D tinged with close to 182C to             182D. Fully opened, upper surface: Between 150D and 155A;             towards the center, tinged with close to 153D; color             becoming closer to 178A tinged with close to 147A with             development. Fully opened, lower surface: Close to 145C;             towards the center and base, between 145B and 147D.         -   Peduncles.—Strength: Moderately strong. Length: About             14.4 cm. Diameter: About 6 mm. Aspect: About 10° from             vertical. Texture: Smooth, glabrous. Color: Close to 146D             tinged with close to 176A.         -   Pedicels.—Strength: Moderately strong. Length: About 1.5 cm.             Diameter: About 2.5 mm. Aspect: About 35° from the axis of             the peduncle. Texture: Smooth, glabrous. Color: Close to             146D tinged with close to 176A.         -   Reproductive organs.—Stamens: Quantity per flower: About 90.             Filament length: About 1.1 cm. Filament color: Close to             145D. Anther shape: Reniform; basifixed. Anther length:             About 1.5 mm. Anther color: Close to 2B. Pollen amount:             Scarce. Pollen color: Close to 2D. Pistils: Quantity per             flower: About five. Pistil length: About 9 mm. Stigma shape:             Club-shaped. Stigma color: Close to N144A. Style length:             About 8 mm. Style color: Close to 145A to 145B. Ovary color:             Close to 145A. Nectaries: Quantity per flower: About ten.             Length: About 7 mm. Diameter, at apex: About 2 mm. Diameter,             at base: About 1 mm. Shape: Tubular. Color: Close to N144C.             Seeds/fruits: Seed and fruit development have not been             observed. -   Garden performance: Plants of the new Helleborus have been observed     to have good garden performance and to tolerate rain, wind and     temperatures from about −20° C. to about 35° C. -   Pathogen/pest resistance: Plants of the new Helleborus have not been     shown to be resistant to pathogens and pests common to Helleborus. 

1. A new and distinct Helleborus plant named ‘Emma’ as illustrated and described. 